Rear-projection screens an affordable option

I’ve heard of plasma and LCD but have recently heard of DLP – can you enlighten me on how DLP is different?

DLP is short for Digital Light Processor. It’s a chip technology from Texas Instruments that is used in rear-projection HDTVs, which are sometimes referred to as RPTVs.

Rear-projection TVs are HDTVs that are not as flat as plasma or LCD TVs. They are a bit bulkier and usually about 18 inches deep or so. They have an internal projection system inside that shines the picture toward you. This lands on the back of the screen you sit in front of. Besides DLP, there are two other rear-projection technologies including LCOS (liquid crystal on silicon) and 3LCD (3-chip Liquid Crystal Display).

Here’s how DLP works. The chip is a microprocessor embedded with millions of tiny micro-mirrors so small that you can’t see them with the naked eye. These mirrors are controlled by the chip to either point away from a light source inside the TV or point toward it. When they point toward it, they reflect light which appears as a white pixel (a dot color that’s part of the TV image) for the TV viewer. If the micro-mirror is pointed away from the light source, it reflects nothing, so a black pixel appears to the TV watcher. The light from the micro-mirrors shine through a spinning color wheel (which gives the light color) and a lens to create an image. The final image is projected toward you onto the back of the TV screen. You watch it from the other side.

The advantage of DLP rear-projection television is that it costs less than similar-sized plasma or LCD flat panels, especially on larger sizes. At a big electronics retailer this fall, 60-inch RPTVs were priced between $2,500 and $3,000, while equivalent-sized plasma screens went for $5,000 to $7,000. Surprisingly enough, Rear-projection TVs are also fairly light. My 50-inch Panasonic DLP, for example, weighs about 80 lbs and is about 18 inches deep. It’s not suited to hang on the wall, but it is easy to move.

If you’re looking for a large-screen, low-cost HDTV, you may want to look at a DLP rear-projection TV. They are big, beautiful, bright and affordable. Find more info on how DLP works at